Okay... this is probably going to be more information than Belinda would like me to reveal, but I'll tell you the main reason she likes having sex with heavier guys vs. skinny guys... it has everything to do with getting off.
Fuck touching bottom. That doesn't do anything for her. She gets off best when riding on top and in control. Fat men have more, well, fat, right about their penis. When she rides her clit grinds into that really well (she prefers her man to be completely bald so the grinding is skin to skin). Gets her off much quicker and better than skinny guys.
And there you have it. AaronM is right again.